Farm-to-Lab project examines the chemistry of food

by MaryAlice Bitts-Jackson

Healthy food is a pathway to a healthy life. But which
foods pack the biggest nutritional punch? Students in a first-year chemistry
class took that question to the lab, measuring nutrients in food
produced at the College
Farm,
compared to supermarket fare.

The experiments, which are just one of the many ways Dickinson incorporates active learning into courses at all levels, were part of a 100-level class taught by Associate Professor of Chemistry Sarah St. Angelo. One included a study of antioxidants such as vitamins A and
C, which have been found to prevent or delay cell damage that can contribute to
health conditions such as infections, cardiovascular disease and some types of
cancer.

After visiting the College Farm to get an up-close
view of day-to-day farm production and trying their hand at various farm
processes, the students designed and conducted original research to determine
which kinds of edibles had the highest levels of antioxidants. And on Nov. 4,
they shared their findings during a poster session in the Rector
Science Complex Atrium.

Confirmations
and surprises

The students had
hypothesized that local, organic fare would be more nutrient rich than
conventionally farmed food. And in nearly all cases, the lab work corroborated
the students’ hypotheses—in some cases, dramatically.

Carlin Smith ’19 and Alex Medeiros ’18, for example, determined that College Farm broccoli
had a full 1.90 times the amount of vitamin C than their conventionally farmed
samples. Hieu Le ’19 and Richard Barron ’19 also uncovered marked differences in
the nutritional values of three different varieties of tea (of the three
samples, green tea was by far the most antioxidant rich).

“I usually
drink green tea anyway,” Le said, looking over his results, which are in tune
with numerous studies worldwide. “After this experiment, I’m definitely going
to continue.”

But there were three research teams that encountered
surprises in the lab.

Lena Friedman ’19 and Haeji Chung ’19 measured changes in the absorption rate of antioxidants in fresh and canned
farm beets, versus fresh and canned store-bought varieties. The fresh College Farm
beets had significantly higher concentrations of antioxidants than the
store-bought, but the farm’s canned beets had slightly lower levels than those
bought at the store.

“That was a big surprise,” said Friedman, who plans to
combine her interests in chemistry and sustainable agriculture, possibly by continuing
this research. “Our guess is that there is a difference in the canning
processes that accounts for the discrepancy.”

Amanda Allan ’19 and Alexandra Ellerkamp ’19 came
to a similar conclusion when they discovered that their samples of
store-bought, organic baby food had comparable—and, in the case of peas,
greater—levels of antioxidants than baby food they made themselves, using
organic ingredients (Ellerkamp believes the team’s cooking processes, and perhaps
manufacturer additives, are to blame).

Data and impact

Matthew Trang ’19 and Maxwell Yoshida ’19 also were taken
aback when they did a comparative analysis of farm and store-bought kale and baby
kale. Trang, who uses farm kale to make smoothies at The
Juice Box, was pleased to discover that farm kale trumps the
store-bought variety, but he was surprised to learn that store-bought baby kale
has the most nutrients of all. He and Yoshida suggested to College Farm staff
that they should harvest kale before it matures, when it is at its nutritional
peak.

Farm Director Jenn Halpin was grateful
for the news. “Having data to support overall health benefits associated with
certain crops grown on our farm provides us with helpful information to share
with customers and helps inform how various production methods impact the
quality of the produce that we grow,” she said. “Research outcomes also prompt
more questions and hypotheses that we hope to investigate further through
future course collaborations and student research.”